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3 years ago

How much heat, in joules, is required to warm a metal disc from 19 °C to 33 °C? The

Chemistry

1 answer:

zalisa [80]3 years ago

3 0

Answer:

Q = 96.6 j

Explanation:

Given data:

Heat required = ?

Initial temperature = 19°C

Final temperature = 33°C

Mass of disc = 3.0 g

Specific heat capacity = 2.3 J/g.°C

Solution:

Specific heat capacity:

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

ΔT = 33°C - 19°C

ΔT = 14°C

Q = 3.0 g×2.3 J/g.°C × 14°C

Q = 96.6 j

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$m_{Pb}C_{Pb}*(T_{eq}-T_{lead}=-m_{H_2O}C_{H_2O}*(T_{eq}-T_{H_2O})\\$

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3 years ago

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3 years ago

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Explanation:

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Atomic number of Cr is 24 and electronic configuration of $Cr$ is [Ar] $4s^{1}3d^{5}$ . This configuration is not stable.

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